The proposed effort is directed toward development of an outcome measure of health care: The Sickness Impact Profile (SIP). The SIP is a scaled measure of sickness-related dysfunctions. Preliminary development during the past two years indicates that a large scale field trial is warrented. Approximately 2500 subjects who are enrollees of the Group Health Cooperative of Puget Sound will be selected for study as part of stratified random sample to be followed for three years. The study is designed to: (1) Finalize the content of the SIP by analyzing subject responses using multivariate techniques. Scaling will be validated by consumer judges. (2) Validate the SIP in relation to appropriate criteria such as measures of utilization, seriousness of illness, and self-assessment of sickness. Relationships between SIP and these criteria will be examined by correlational and analysis of variance procedures. (3) Determine the sensitivity or discriminative capability of the SIP by following patients within specific diagnostic entities. Clinical ratings of dysfunction and/or pathology based on clinical data will be correlated with SIP scores as subjects are followed over the course of their illness. (4) Assess the potential usefulness of the SIP in providing information relevant to the evalution of a health care program. The relationship between length of enrollment and SIP scores will be analyzed, comparing longitudinal and cross- sectional trends. (5) Explore alternative administrative procedures. Self-administration and use of surrogate respondents will be tested by analyzing reliability and comparative validity.